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J C Vernant

Publications and source records attributed to J C Vernant.

At least 19 recordsLinked to original sources

MS and neuromyelitis optica in Martinique (French West Indies).

BACKGROUND AND OBJECTIVE: A population-based study is reported of MS in French Afro-Caribbeans (FAC) in Martinique. FAC are descendants of interracial mating that occurred between French Caucasians and black Africans in the 17th and the 18th centuries. METHODS: The authors surveyed the entire island of Martinique (area 1,128 km(2), population 357,000) between November 1997 and October 1999. RESULTS: Sixty-two patients (46 females, 16 males, ratio 2.9:1) were identified with definite or probable disease by the Poser criteria. Prevalence for all patients on December 31, 1998, was 17.4/10(5) (95% CI 13.1 to 21.7) and 14.3/10(5) (95% CI 10.4 to 18.2) for clinically definite cases (n = 51). Age range of patients on prevalence day was 17 to 73 years (mean +/- SD 39 +/- 11.3 years). Mean age at onset was 31.2 +/- 11 years. Overall, 9.7% had primary progressive disease and 19.4% had benign MS. A low proportion of definite and probable MS cases had oligoclonal bands in CSF (50.9%). Seventeen patients, 13 of whom were alive on prevalence day, had a relapsing form of neuromyelitis optica. CONCLUSION: The island of Martinique appears to have a low to medium prevalence of MS. MS was almost unknown in FAC in Martinique until the late 1970s. The apparent recent increase may be explained by improved recognition of patients, increased availability of MRI for diagnosis, increased disease awareness among physicians, increased survival of MS patients, or an actual increase in disease frequency.

Adolescent↗

Seroindeterminate patterns and seroconversions to human T-lymphotropic virus type I positivity in blood donors from Martinique, French West Indies.

BACKGROUND: Screening for human T-lymphotropic virus type I (HTLV-I) antibodies in volunteer blood donors has been systematic in the French West Indies since 1989. Western blot-indeterminate results are commonly obtained. The significance of these indeterminate serologic patterns in HTLV-I-endemic areas is still unclear. STUDY DESIGN AND METHODS: During a 2-year period, 9759 blood donors were tested for HTLV-I antibodies. The epidemiologic features of HTLV-I-seropositive, -seroindeterminate, and -seronegative donors were compared. A lookback investigation was performed for the HTLV-I-seropositive donors, and the HTLV-I-seroindeterminate individuals were followed up. RESULTS: Thirty-nine donors (0.4%) were HTLV-I seropositive and 49 (0.5%) were seroindeterminate. The age and sex ratio characteristics of the seroindeterminate donors are divergent from those of the HTLV-I-seropositive group and are more like those of the seronegative population. However, during the study period, three cases of seroconversion after an initial seroindeterminate profile were reported. Two cases were detected through follow-up of 38 HTLV-I-seroindeterminate donors over a mean of 8 months (2-24 months). The third seroconverter belonged to the HTLV-I-seropositive group and was identified through lookback investigation. This case is atypical, with p19 reactivity for several months before HTLV-I seropositivity. CONCLUSION: These findings indicate that, although HTLV-I-seroindeterminate donors mainly are HTLV-I-noninfected, the rate of seroconversion in a repeat blood donor population from an endemic region must be taken into consideration. Moreover, the case of delayed seroconversion observed in this study suggests the difficulty of counseling seroindeterminate blood donors in endemic regions.

Adult↗

Human T cell leukemia virus type I expression in salivary glands of infected patients.

Human T cell leukemia virus type I (HTLV-I) sequences were sought in labial salivary glands of patients with HTLV-I-associated myelopathy or tropical spastic paraparesis and of seropositive neurologically healthy carriers. HTLV-I proviral DNA was found by polymerase chain reaction amplification in DNA extracted from lip biopsies of every patient. Viral RNA was found by in situ hybridization in the acini epithelium, as well as in lymphocytic infiltrates. This observation suggests that HTLV-I expression in labial salivary glands could participate in the inflammatory lesions observed in these patients. Some seronegative patients with Sjögren's syndrome or dryness syndrome were also positive for viral transactivator tax DNA (41% in Martinique and 16% in non-HTLV-I-endemic region). Despite histologic signs of lymphocytic infiltration, no viral expression was found in the labial salivary glands of these patients.

Carrier State↗

[Epileptic seizures, epilepsy and risk factors. Experiences with an investigation in Martinique. Epimart Group].

A prospective incidence study was carried out in the French Caribbean island of Martinique between May 1st 1994 and April 31st 1995. incidence was 80.6 (77.7 when standardized with 1990 U.S. population). This incidence was higher than that observed in the Swiss canton of Geneva where the same methodology was used. The individualized risk factors of first provoked and unprovoked seizures in Martinique were alcoholism, head trauma and cerebro-vascular accidents.

Epilepsy↗

Molecular and clinical correlations in spinocerebellar ataxia 2: a study of 32 families.

Spinocerebellar ataxia 2 (SCA2) is caused by the expansion of an unstable CAG repeat encoding a polyglutamine tract. One hundred and eighty four index patients with autosomal dominant cerebellar ataxia type I were screened for this mutation. We found expansion in 109 patients from 30 families of different geographical origins (15%) and in two isolated cases with no known family histories (2%). The SCA2 chromosomes contained from 34 to 57 repeats and consisted of a pure stretch of CAG, whereas all tested normal chromosomes (14-31 repeats), except one with 14 repeats, were interrupted by 1-3 repeats of CAA. As in other diseases caused by unstable mutations, a strong negative correlation was observed between the age at onset and the size of the CAG repeat (r = -0.81). The frequency of several clinical signs such as myoclonus, dystonia and myokymia increased with the number of CAG repeats whereas the frequency of others was related to disease duration. The CAG repeat was highly unstable during transmission with variations ranging from -8 to +12, and a mean increase of +2.2, but there was no significant difference according to the parental sex. This instability was confirmed by the high degree of gonadal mosaicism observed in sperm DNA of one patient.

Adolescent↗

Recurrent optic neuromyelitis with endocrinopathies: a new syndrome.

We report a new syndrome that we call "recurrent optic neuromyelitis with endocrinopathies" in eight Antillean women from Martinique and Guadeloupe Ocular involvement was either monocular or binocular, whereas myelopathy was acute or subacute. In seven patients, myelopathic symptoms recurred, and in six patients, visual problems recurred. Spinal cord involvement was a consistent band-like pseudo-syringomyelic dissociated sensory loss. All eight patients had endocrinopathies consisting of amenorrhea, galactorrhea, diabetes insipidus, hypothyroidism, or hyperphagia. Spinal cord MRI revealed cavitation-like images. Various immunosuppressant treatments had little effect on the uniformly deteriorating course, ending in blindness and paraplegia. Six patients died within 5 years of onset, and an autopsy in one patient showed multiple demyelinizing lesions of the spinal cord with thickened blood vessels walls without evidence of inflammation. These cases appear to constitute a syndrome distinct from MS and from classic Devic's syndrome, not only because of the association with endocrinopathies but because of the stereotypy of the recurrences, the absence of MRI lesions in the cerebral white matter, and the unusual image of cavitation of the spinal cord. The syndrome is also distinct from HTLV-I-associated paraparesis, which is endemic in the West Indies.

Adolescent↗

[Extensive cerebral venous thrombosis resistant to heparin: local fibrinolysis with urokinase].

A 37 year-old man had headaches for 10 days, then a single tonic-clonic seizure and coma due to an extensive cerebral venous thrombosis. In spite of full-dose heparin treatment for 7 days, the clinical picture worsened along with increasing edema on CT-Scan. Direct thrombolytic treatment was then performed using transvenous catheterization and instillation of Urokinase (2.6 MU over 4 days). A near complete repermeabilization of the sinuses was obtained and the patient improved dramatically in a few days. The only adverse effect of Urokinase was hematuria. Based on our experience and review of the literature which includes 26 previous cases, direct thrombolytic therapy appears to be a relatively safe procedure. This treatment should be considered in a patient with extensive dural sinus thrombosis which fails to respond to heparin treatment.

Adult↗

Autosomal dominant cerebellar ataxia type I in Martinique (French West Indies): genetic analysis of three unrelated SCA2 families.

Autosomal dominant cerebellar ataxias (ADCAs) are a group of neurodegenerative disorders that are clinically and genetically heterogeneous. We report here a genetic linkage study, with five chromosome 12q markers, of three Martinican families with ADCA type 1, for which the spinocerebellar ataxia 1 (SCA1) locus was excluded. Linkage to the SCA2 locus was demonstrated with a maximal lead score of 6.64 at theta = 0.00 with marker D12S354. Recombinational events observed by haplotype reconstruction demonstrated that the SCA2 locus is located in an approximately 7-cM interval flanked by D12S105 and D12S79. Using the z(max)-1 method, multipoint analysis further reduced the candidate interval for SCA2 to a region of 5 cM. Two families shared a common haplotype at loci spanning 7 cM, which suggests a founder effect, whereas a different haplotype segregated with the disease in the third family. Finally, a mean anticipation of 12+/-14 years was found in parent-child couples, with no parental sex effect, suggesting that the disease might be caused by an expanded and unstable triplet repeat.

Adolescent↗

Complement-dependent cytotoxic antibodies to human T lymphotropic virus type I (HTLV-I)-infected cells in the sera of HTLV-I-infected individuals.

To investigate whether HTLV-I induces the development of complement-dependent cytotoxic antibodies in humans, sera of asymptomatic HTLV-I carriers and of patients suffering from tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) or adult T cell leukaemia (ATL) were used in a cytotoxicity assay against a panel of target cells. This panel included uninfected cell lines (CEM, Jurkat, Molt and H9), cell lines chronically infected with HTLV-I (MT2, MT4, C9IPL and HUT102), as well as lines H36 (H9 infected with HTLV-I), H9-IIIB (H9 infected with HIVms) and H9-MN (H9 infected with HIMVMN). HTLV-I+ sera induced lysis of H36 and of lines expressing HTLV-I antigens in the presence of rabbit complement, but did not lyse cells in presence of human complement. The HTLV-I+ sera also failed to lyse the HTLV-I- lines and H9 cells, suggesting that lysis was specific for HTLV-I. H36 cell lysis was prevented by IgG depletion of the sera and by dialysis of rabbit complement against EGTA or EDTA. Rabbit complement-dependent cytotoxic antibodies were present in the sera of 14/14 HTLV-I-infected individuals; the highest titres were predominantly found in the sera of the TSP/HAM patients. Such antibodies were also detected in 5/5 individuals coinfected with HIV-1 and HTLV-I, although no cytotoxic antibody could be found against HIV-infected cells. Vice versa, sera of HIV-1-infected individuals did not exert a lytic effect in the presence of complement (of human or rabbit origin) against HIV-1- or HTLV-I-infected cells. Incubation of the sera of four HTLV-I-infected patients with HTLV-I env-specific synthetic peptides demonstrated that some of the complement-dependent cytotoxic antibodies recognized epitopes located on gp46 between amino acids 190 and 209. There is no correlation of rabbit complement-dependent cytotoxic HTLV-I antibodies with the development of disease.

Antibodies, Viral↗

Ocular manifestations in patients with HTLV-I associated infection--a clinical study of 93 cases.

The purpose of this study was to confirm that ophthalmological features seen in patients in Martinique, French West Indies, could be linked to infection by HTLV-I. The authors studied 93 HTLV-I infected patients divided into 70 patients with HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP) and 23 asymptomatic HTLV-I carriers. They did a complete ophthalmological examination with an assessment of lacrymal secretion by means of three tests: Shirmer 1, break-up time and rose Bengal. Some patients had a biopsy of secondary salivary glands. When possible, detection of HTLV-I antibodies was carried out in the aqueous humor. In 45 of the 93 patients (48.4%) the presence of dry keratoconjunctivitis was recorded. In 22 of these 45 cases, a biopsy of the secondary salivary glands showed the presence of lymphoplasmocytoid infiltrations comparable to the glandular changes that occur with Gougerot-Sjögren syndrome. Among the 93 patients, 15 cases of uveitis were noted (16.1%) with 13 cases of anterior uveitis and 11 cases of vitritis. The inflammation was bilateral in 9 cases (9/15 = 60%). Two cases of cotton wool spots, 3 cases of abnormalities in the distribution of the retinal pigment and 7 cases of corneal lesions were also noted. Higher levels of anti-HTLV-I antibodies were detected in the aqueous humor of 3 patients with uveitis. The coexistence of dry eye (keratoconjunctivitis), uveitis and retinal microangiopathy in patients who are suffering from HAM/TSP could suggest the involvement of an autoimmune or immunological mechanism in the physiopathology of the illness.

Adult↗

[Sjögren's syndrome and HTLV-I myelopathy].

The objective of this study is to describe the clinical and immunological aspects observed in patients with both "tropical spastic paraparesis/HTLV-I associated myelopathy" (TSP/HAM) and ocular dryness. In 10 such patients clinical and biological examinations completed with a biopsy of secondary salivary glands were performed to assess the etiology of the ocular dryness. According to the Chisholm's scale, 70% of the patients had a biopsy grade 3 or grade 4. Polyclonal hypergammaglobulinemia was found in 90% of patients and lymphocytic alveolitis in 80%. Three patients had past medical history of chronic uveltis. All the findings were compatible with Sjögren's syndrome, however no characteristic immunological disorders were found. Antinuclear antibodies and rheumatoid factor proved negative in all cases.

Adult↗